linux/drivers/hwmon/ibmpowernv.c
Takashi Iwai 6a096871b2 hwmon: (ibmpowernv) Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-03-11 08:09:31 -07:00

720 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* IBM PowerNV platform sensors for temperature/fan/voltage/power
* Copyright (C) 2014 IBM
*/
#define DRVNAME "ibmpowernv"
#define pr_fmt(fmt) DRVNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <asm/opal.h>
#include <linux/err.h>
#include <asm/cputhreads.h>
#include <asm/smp.h>
#define MAX_ATTR_LEN 32
#define MAX_LABEL_LEN 64
/* Sensor suffix name from DT */
#define DT_FAULT_ATTR_SUFFIX "faulted"
#define DT_DATA_ATTR_SUFFIX "data"
#define DT_THRESHOLD_ATTR_SUFFIX "thrs"
/*
* Enumerates all the types of sensors in the POWERNV platform and does index
* into 'struct sensor_group'
*/
enum sensors {
FAN,
TEMP,
POWER_SUPPLY,
POWER_INPUT,
CURRENT,
ENERGY,
MAX_SENSOR_TYPE,
};
#define INVALID_INDEX (-1U)
/*
* 'compatible' string properties for sensor types as defined in old
* PowerNV firmware (skiboot). These are ordered as 'enum sensors'.
*/
static const char * const legacy_compatibles[] = {
"ibm,opal-sensor-cooling-fan",
"ibm,opal-sensor-amb-temp",
"ibm,opal-sensor-power-supply",
"ibm,opal-sensor-power"
};
static struct sensor_group {
const char *name; /* matches property 'sensor-type' */
struct attribute_group group;
u32 attr_count;
u32 hwmon_index;
} sensor_groups[] = {
{ "fan" },
{ "temp" },
{ "in" },
{ "power" },
{ "curr" },
{ "energy" },
};
struct sensor_data {
u32 id; /* An opaque id of the firmware for each sensor */
u32 hwmon_index;
u32 opal_index;
enum sensors type;
char label[MAX_LABEL_LEN];
char name[MAX_ATTR_LEN];
struct device_attribute dev_attr;
struct sensor_group_data *sgrp_data;
};
struct sensor_group_data {
struct mutex mutex;
u32 gid;
bool enable;
};
struct platform_data {
const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
struct sensor_group_data *sgrp_data;
u32 sensors_count; /* Total count of sensors from each group */
u32 nr_sensor_groups; /* Total number of sensor groups */
};
static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_data *sdata = container_of(devattr, struct sensor_data,
dev_attr);
ssize_t ret;
u64 x;
if (sdata->sgrp_data && !sdata->sgrp_data->enable)
return -ENODATA;
ret = opal_get_sensor_data_u64(sdata->id, &x);
if (ret)
return ret;
/* Convert temperature to milli-degrees */
if (sdata->type == TEMP)
x *= 1000;
/* Convert power to micro-watts */
else if (sdata->type == POWER_INPUT)
x *= 1000000;
return sprintf(buf, "%llu\n", x);
}
static ssize_t show_enable(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_data *sdata = container_of(devattr, struct sensor_data,
dev_attr);
return sprintf(buf, "%u\n", sdata->sgrp_data->enable);
}
static ssize_t store_enable(struct device *dev,
struct device_attribute *devattr,
const char *buf, size_t count)
{
struct sensor_data *sdata = container_of(devattr, struct sensor_data,
dev_attr);
struct sensor_group_data *sgrp_data = sdata->sgrp_data;
int ret;
bool data;
ret = kstrtobool(buf, &data);
if (ret)
return ret;
ret = mutex_lock_interruptible(&sgrp_data->mutex);
if (ret)
return ret;
if (data != sgrp_data->enable) {
ret = sensor_group_enable(sgrp_data->gid, data);
if (!ret)
sgrp_data->enable = data;
}
if (!ret)
ret = count;
mutex_unlock(&sgrp_data->mutex);
return ret;
}
static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_data *sdata = container_of(devattr, struct sensor_data,
dev_attr);
return sprintf(buf, "%s\n", sdata->label);
}
static int get_logical_cpu(int hwcpu)
{
int cpu;
for_each_possible_cpu(cpu)
if (get_hard_smp_processor_id(cpu) == hwcpu)
return cpu;
return -ENOENT;
}
static void make_sensor_label(struct device_node *np,
struct sensor_data *sdata, const char *label)
{
u32 id;
size_t n;
n = scnprintf(sdata->label, sizeof(sdata->label), "%s", label);
/*
* Core temp pretty print
*/
if (!of_property_read_u32(np, "ibm,pir", &id)) {
int cpuid = get_logical_cpu(id);
if (cpuid >= 0)
/*
* The digital thermal sensors are associated
* with a core.
*/
n += scnprintf(sdata->label + n,
sizeof(sdata->label) - n, " %d",
cpuid);
else
n += scnprintf(sdata->label + n,
sizeof(sdata->label) - n, " phy%d", id);
}
/*
* Membuffer pretty print
*/
if (!of_property_read_u32(np, "ibm,chip-id", &id))
n += scnprintf(sdata->label + n, sizeof(sdata->label) - n,
" %d", id & 0xffff);
}
static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
{
char *hash_pos = strchr(name, '#');
char buf[8] = { 0 };
char *dash_pos;
u32 copy_len;
int err;
if (!hash_pos)
return -EINVAL;
dash_pos = strchr(hash_pos, '-');
if (!dash_pos)
return -EINVAL;
copy_len = dash_pos - hash_pos - 1;
if (copy_len >= sizeof(buf))
return -EINVAL;
strncpy(buf, hash_pos + 1, copy_len);
err = kstrtou32(buf, 10, index);
if (err)
return err;
strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
return 0;
}
static const char *convert_opal_attr_name(enum sensors type,
const char *opal_attr)
{
const char *attr_name = NULL;
if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
attr_name = "fault";
} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
attr_name = "input";
} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
if (type == TEMP)
attr_name = "max";
else if (type == FAN)
attr_name = "min";
}
return attr_name;
}
/*
* This function translates the DT node name into the 'hwmon' attribute name.
* IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
* which need to be mapped as fan2_input, temp1_max respectively before
* populating them inside hwmon device class.
*/
static const char *parse_opal_node_name(const char *node_name,
enum sensors type, u32 *index)
{
char attr_suffix[MAX_ATTR_LEN];
const char *attr_name;
int err;
err = get_sensor_index_attr(node_name, index, attr_suffix);
if (err)
return ERR_PTR(err);
attr_name = convert_opal_attr_name(type, attr_suffix);
if (!attr_name)
return ERR_PTR(-ENOENT);
return attr_name;
}
static int get_sensor_type(struct device_node *np)
{
enum sensors type;
const char *str;
for (type = 0; type < ARRAY_SIZE(legacy_compatibles); type++) {
if (of_device_is_compatible(np, legacy_compatibles[type]))
return type;
}
/*
* Let's check if we have a newer device tree
*/
if (!of_device_is_compatible(np, "ibm,opal-sensor"))
return MAX_SENSOR_TYPE;
if (of_property_read_string(np, "sensor-type", &str))
return MAX_SENSOR_TYPE;
for (type = 0; type < MAX_SENSOR_TYPE; type++)
if (!strcmp(str, sensor_groups[type].name))
return type;
return MAX_SENSOR_TYPE;
}
static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
struct sensor_data *sdata_table, int count)
{
int i;
/*
* We don't use the OPAL index on newer device trees
*/
if (sdata->opal_index != INVALID_INDEX) {
for (i = 0; i < count; i++)
if (sdata_table[i].opal_index == sdata->opal_index &&
sdata_table[i].type == sdata->type)
return sdata_table[i].hwmon_index;
}
return ++sensor_groups[sdata->type].hwmon_index;
}
static int init_sensor_group_data(struct platform_device *pdev,
struct platform_data *pdata)
{
struct sensor_group_data *sgrp_data;
struct device_node *groups, *sgrp;
int count = 0, ret = 0;
enum sensors type;
groups = of_find_compatible_node(NULL, NULL, "ibm,opal-sensor-group");
if (!groups)
return ret;
for_each_child_of_node(groups, sgrp) {
type = get_sensor_type(sgrp);
if (type != MAX_SENSOR_TYPE)
pdata->nr_sensor_groups++;
}
if (!pdata->nr_sensor_groups)
goto out;
sgrp_data = devm_kcalloc(&pdev->dev, pdata->nr_sensor_groups,
sizeof(*sgrp_data), GFP_KERNEL);
if (!sgrp_data) {
ret = -ENOMEM;
goto out;
}
for_each_child_of_node(groups, sgrp) {
u32 gid;
type = get_sensor_type(sgrp);
if (type == MAX_SENSOR_TYPE)
continue;
if (of_property_read_u32(sgrp, "sensor-group-id", &gid))
continue;
if (of_count_phandle_with_args(sgrp, "sensors", NULL) <= 0)
continue;
sensor_groups[type].attr_count++;
sgrp_data[count].gid = gid;
mutex_init(&sgrp_data[count].mutex);
sgrp_data[count++].enable = false;
}
pdata->sgrp_data = sgrp_data;
out:
of_node_put(groups);
return ret;
}
static struct sensor_group_data *get_sensor_group(struct platform_data *pdata,
struct device_node *node,
enum sensors gtype)
{
struct sensor_group_data *sgrp_data = pdata->sgrp_data;
struct device_node *groups, *sgrp;
groups = of_find_compatible_node(NULL, NULL, "ibm,opal-sensor-group");
if (!groups)
return NULL;
for_each_child_of_node(groups, sgrp) {
struct of_phandle_iterator it;
u32 gid;
int rc, i;
enum sensors type;
type = get_sensor_type(sgrp);
if (type != gtype)
continue;
if (of_property_read_u32(sgrp, "sensor-group-id", &gid))
continue;
of_for_each_phandle(&it, rc, sgrp, "sensors", NULL, 0)
if (it.phandle == node->phandle) {
of_node_put(it.node);
break;
}
if (rc)
continue;
for (i = 0; i < pdata->nr_sensor_groups; i++)
if (gid == sgrp_data[i].gid) {
of_node_put(sgrp);
of_node_put(groups);
return &sgrp_data[i];
}
}
of_node_put(groups);
return NULL;
}
static int populate_attr_groups(struct platform_device *pdev)
{
struct platform_data *pdata = platform_get_drvdata(pdev);
const struct attribute_group **pgroups = pdata->attr_groups;
struct device_node *opal, *np;
enum sensors type;
int ret;
ret = init_sensor_group_data(pdev, pdata);
if (ret)
return ret;
opal = of_find_node_by_path("/ibm,opal/sensors");
for_each_child_of_node(opal, np) {
const char *label;
type = get_sensor_type(np);
if (type == MAX_SENSOR_TYPE)
continue;
sensor_groups[type].attr_count++;
/*
* add attributes for labels, min and max
*/
if (!of_property_read_string(np, "label", &label))
sensor_groups[type].attr_count++;
if (of_find_property(np, "sensor-data-min", NULL))
sensor_groups[type].attr_count++;
if (of_find_property(np, "sensor-data-max", NULL))
sensor_groups[type].attr_count++;
}
of_node_put(opal);
for (type = 0; type < MAX_SENSOR_TYPE; type++) {
sensor_groups[type].group.attrs = devm_kcalloc(&pdev->dev,
sensor_groups[type].attr_count + 1,
sizeof(struct attribute *),
GFP_KERNEL);
if (!sensor_groups[type].group.attrs)
return -ENOMEM;
pgroups[type] = &sensor_groups[type].group;
pdata->sensors_count += sensor_groups[type].attr_count;
sensor_groups[type].attr_count = 0;
}
return 0;
}
static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
ssize_t (*show)(struct device *dev,
struct device_attribute *attr,
char *buf),
ssize_t (*store)(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count))
{
snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
sensor_groups[sdata->type].name, sdata->hwmon_index,
attr_name);
sysfs_attr_init(&sdata->dev_attr.attr);
sdata->dev_attr.attr.name = sdata->name;
sdata->dev_attr.show = show;
if (store) {
sdata->dev_attr.store = store;
sdata->dev_attr.attr.mode = 0664;
} else {
sdata->dev_attr.attr.mode = 0444;
}
}
static void populate_sensor(struct sensor_data *sdata, int od, int hd, int sid,
const char *attr_name, enum sensors type,
const struct attribute_group *pgroup,
struct sensor_group_data *sgrp_data,
ssize_t (*show)(struct device *dev,
struct device_attribute *attr,
char *buf),
ssize_t (*store)(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count))
{
sdata->id = sid;
sdata->type = type;
sdata->opal_index = od;
sdata->hwmon_index = hd;
create_hwmon_attr(sdata, attr_name, show, store);
pgroup->attrs[sensor_groups[type].attr_count++] = &sdata->dev_attr.attr;
sdata->sgrp_data = sgrp_data;
}
static char *get_max_attr(enum sensors type)
{
switch (type) {
case POWER_INPUT:
return "input_highest";
default:
return "highest";
}
}
static char *get_min_attr(enum sensors type)
{
switch (type) {
case POWER_INPUT:
return "input_lowest";
default:
return "lowest";
}
}
/*
* Iterate through the device tree for each child of 'sensors' node, create
* a sysfs attribute file, the file is named by translating the DT node name
* to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
* etc..
*/
static int create_device_attrs(struct platform_device *pdev)
{
struct platform_data *pdata = platform_get_drvdata(pdev);
const struct attribute_group **pgroups = pdata->attr_groups;
struct device_node *opal, *np;
struct sensor_data *sdata;
u32 count = 0;
u32 group_attr_id[MAX_SENSOR_TYPE] = {0};
sdata = devm_kcalloc(&pdev->dev,
pdata->sensors_count, sizeof(*sdata),
GFP_KERNEL);
if (!sdata)
return -ENOMEM;
opal = of_find_node_by_path("/ibm,opal/sensors");
for_each_child_of_node(opal, np) {
struct sensor_group_data *sgrp_data;
const char *attr_name;
u32 opal_index, hw_id;
u32 sensor_id;
const char *label;
enum sensors type;
type = get_sensor_type(np);
if (type == MAX_SENSOR_TYPE)
continue;
/*
* Newer device trees use a "sensor-data" property
* name for input.
*/
if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
of_property_read_u32(np, "sensor-data", &sensor_id)) {
dev_info(&pdev->dev,
"'sensor-id' missing in the node '%pOFn'\n",
np);
continue;
}
sdata[count].id = sensor_id;
sdata[count].type = type;
/*
* If we can not parse the node name, it means we are
* running on a newer device tree. We can just forget
* about the OPAL index and use a defaut value for the
* hwmon attribute name
*/
attr_name = parse_opal_node_name(np->name, type, &opal_index);
if (IS_ERR(attr_name)) {
attr_name = "input";
opal_index = INVALID_INDEX;
}
hw_id = get_sensor_hwmon_index(&sdata[count], sdata, count);
sgrp_data = get_sensor_group(pdata, np, type);
populate_sensor(&sdata[count], opal_index, hw_id, sensor_id,
attr_name, type, pgroups[type], sgrp_data,
show_sensor, NULL);
count++;
if (!of_property_read_string(np, "label", &label)) {
/*
* For the label attribute, we can reuse the
* "properties" of the previous "input"
* attribute. They are related to the same
* sensor.
*/
make_sensor_label(np, &sdata[count], label);
populate_sensor(&sdata[count], opal_index, hw_id,
sensor_id, "label", type, pgroups[type],
NULL, show_label, NULL);
count++;
}
if (!of_property_read_u32(np, "sensor-data-max", &sensor_id)) {
attr_name = get_max_attr(type);
populate_sensor(&sdata[count], opal_index, hw_id,
sensor_id, attr_name, type,
pgroups[type], sgrp_data, show_sensor,
NULL);
count++;
}
if (!of_property_read_u32(np, "sensor-data-min", &sensor_id)) {
attr_name = get_min_attr(type);
populate_sensor(&sdata[count], opal_index, hw_id,
sensor_id, attr_name, type,
pgroups[type], sgrp_data, show_sensor,
NULL);
count++;
}
if (sgrp_data && !sgrp_data->enable) {
sgrp_data->enable = true;
hw_id = ++group_attr_id[type];
populate_sensor(&sdata[count], opal_index, hw_id,
sgrp_data->gid, "enable", type,
pgroups[type], sgrp_data, show_enable,
store_enable);
count++;
}
}
of_node_put(opal);
return 0;
}
static int ibmpowernv_probe(struct platform_device *pdev)
{
struct platform_data *pdata;
struct device *hwmon_dev;
int err;
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
platform_set_drvdata(pdev, pdata);
pdata->sensors_count = 0;
pdata->nr_sensor_groups = 0;
err = populate_attr_groups(pdev);
if (err)
return err;
/* Create sysfs attribute data for each sensor found in the DT */
err = create_device_attrs(pdev);
if (err)
return err;
/* Finally, register with hwmon */
hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
pdata,
pdata->attr_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct platform_device_id opal_sensor_driver_ids[] = {
{
.name = "opal-sensor",
},
{ }
};
MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
static const struct of_device_id opal_sensor_match[] = {
{ .compatible = "ibm,opal-sensor" },
{ },
};
MODULE_DEVICE_TABLE(of, opal_sensor_match);
static struct platform_driver ibmpowernv_driver = {
.probe = ibmpowernv_probe,
.id_table = opal_sensor_driver_ids,
.driver = {
.name = DRVNAME,
.of_match_table = opal_sensor_match,
},
};
module_platform_driver(ibmpowernv_driver);
MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
MODULE_DESCRIPTION("IBM POWERNV platform sensors");
MODULE_LICENSE("GPL");